README.md

Line & Polygon Editor for flutter_map

A basic line and polygon editor that works with flutter_map, relying on DragMarker from flutter_map_dragmarker.

Getting started

To use this package, first add flutter_map_line_editor as a dependency in your pubspec.yaml file:

dependencies:
  flutter_map_line_editor: <latest version>

See the example directory for a complete example app demonstrating the usage of this package, here are the most important features:

• Tap the map to add a marker, add as many as you want.
• Drag the main points to move them.
• Drag the intermediate points to create a new point there and drag to where you want.
• Long press to delete a point.

Usage

Once the package is installed, make sure to import the package in the file that you are going to need it, you may also need to import flutter_map_dragmarker:

import 'package:flutter_map_dragmarker/flutter_map_dragmarker.dart';
import 'package:flutter_map_line_editor/flutter_map_line_editor.dart';

Set up a new editor instance, tipically inside initState():

var polyEditor = PolyEditor(
  points: testPolyline.points,
  pointIcon: Icon(Icons.crop_square, size: 23),
  intermediateIcon: Icon(Icons.lens, size: 15, color: Colors.grey),
  callbackRefresh: () => { this.setState(() {})},
  addClosePathMarker: false, // set to true if polygon
);

The PolyEditor takes a list of LatLng points that are used to put DragMarker's over these locations. PolyEditor does not care if the given list of points is a polyline, it could be something else. This list will be edited in place so that when the build method is triggered it will use updated points.

You must also pass a Widget (tipically an Icon) using the pointIcon parameter that will be used to represent each DragMarker.

You may also pass the optional parameter intermediateIconto display another DragMarker halfway between the main points. Dragging this marker will create another main point and the line will be split.

The screen needs to be updated during a drag, so callbackRefresh takes a function that will get called each drag frame.

For polygons or “closed paths” set the parameter addClosePathMarker to true so that the end auto-returns to the start. Otherwise, if you just want a basic polyline, set this to false.

You can add a point programmatically using the onTap callback in MapOptions:

onTap: (ll) {
  polyEditor.add(testPolyline.points, ll);
},

Add the correspondent layers as FlutterMap childrens:

FlutterMap(
  options: MapOptions(
    onTap: (_, ll) {
      polyEditor.add(testPolyline.points, ll);
    },
  ),
  children: [
    // .....
    PolylineLayer(polylines: polyLines),
    DragMarkers(markers: polyEditor.edit()),
  ],
),

Report issues or feature requests in the GitHub repository, Pull Requests are welcome!

License

This package is licensed under the permissive MIT License. See the LICENSE file in this repository to get a full copy.